Ampicillin Soluble Powder
» Ampicillin Soluble Powder is a dry mixture of Ampicillin (as the trihydrate) and one or more suitable diluents and stabilizing agents. It contains not less than 90.0 percent and not more than 120.0 percent of the labeled amount of ampicillin (C16H19N3O4S).
Packaging and storage— Preserve in tight containers.
Labeling— Label it to indicate that it is for veterinary use only.
Identification— Dissolve a quantity of it in a mixture of acetone and 0.1 N hydrochloric acid (4:1) to obtain a solution containing 10 mg of ampicillin per mL: the resulting solution responds to the Identification test under Ampicillin Capsules.
pH 791: between 3.5 and 6.0, in an aqueous solution containing the equivalent of 20 mg of ampicillin per mL.
Water, Method I 921: not more than 5.0%.
Assay—
Standard preparation— Prepare as directed for Standard Preparation under Iodometric Assay—Antibiotics 425, using USP Ampicillin RS.
Assay preparation— Transfer an accurately weighed quantity of Soluble Powder, equivalent to about 125 mg of ampicillin, to a 100-mL volumetric flask, dissolve in and dilute with water to volume, and mix.
Procedure— Proceed as directed for Procedure under Iodometric Assay—Antibiotics 425. Calculate the quantity, in mg, of ampicillin (C16H19N3O4S) in the portion of Soluble Powder taken by the formula:
(F / 20)(B I).
Auxiliary Information— Please check for your question in the FAQs before contacting USP.
Topic/Question Contact Expert Committee
Monograph Ian DeVeau, Ph.D.
Director, Veterinary Drugs and Radiopharmaceuticals
1-301-816-8178
(VET05) Veterinary Drugs 05
Reference Standards Lili Wang, Technical Services Scientist
1-301-816-8129
RSTech@usp.org
USP32–NF27 Page 1551